1. Field of the Invention
This invention relates to a device for gathering cable on a mining machine and more particularly to a cable gathering device for loosely confining multi-conductor electrical cable in a random configuration within an enclosed storage compartment on the mining machine.
2. Description of the Prior Art
In underground mining the vehicle used to transport the dislodged material from a continuously advancing mining machine to a fixed transportation means, such as a conveyor, is a mobile vehicle propelled by electric motors. A specific example of such an electrically propelled mobile haulage vehicle is a shuttle car which receives power through a single conductor or a multi-conductor trailing cable. The electrical cable is connected at one end to a fixed source of power and at the other end to a cable reel that is rotatably secured to the frame of the vehicle. The conventional cable reel is positioned laterally on one side of the vehicle. A spooling device is provided to uniformly locate the cable on the cable reel as the vehicle advances toward the source of power. The conventional cable reel and spooling devices are expensive and subject the cable when wound tightly on the reel to excessive side wear which may result in destruction of the cable insulation and the hazard of fire by sparking or arcing across exposed conductors. Furthermore, the tension generated in the cable as it is reeled onto the cable reel tends to weaken the tensile strength of the cable subjecting it to malfunction by parting due to the excessive tensile forces generated especially when the vehicle suddenly changes direction.
Take-up devices for telephone and electric lamp wires or cord which eliminate the need for reel and spooling devices in handling the slack wire are known in the art. U.S. Pat. No. 1,865,069 illustrates and describes an improved take-up device for electric wires, cords and the like which includes a receptacle for storing slack wire for telephone. The wire leads out of the receptacle through an opening and is attached at one end to the telephone. The portion of the wire extending through the opening is frictionally engaged to a pair of co-acting rollers, which rotate by virtue of the frictional engagement with the wire. The rollers are non-rotatably connected through gear members to a spring. Rotation of the rollers through the gear members places the spring under tension when the telephone is lifted and pulled outwardly. When the telephone is again placed on its stand adjacent the storage receptacle the spring rotates the gear members in an opposite direction to, in turn, rotate the rollers and pull the wire inwardly into the receptacle. With this arrangement, the problem of accommodating loose telephone wire or floor lamp cord on the floor is alleviated.
There is need for a cable gathering device to convey cable to and from a mobile mining machine as it is operated in a mine that eliminates the forces exerted upon the cable by the excessive weight of conventional cable reel and spooling devices and surges in tension that occur when a vehicle suddenly changes direction. While it has been suggested by the prior art systems to provide alternatives to cable reels and spools for conveying cable from a receptacle by rollers frictionally engaging the cable, there is need for a cable gathering device that selectively conveys the cable to and from the storage receptacle to permit movement of the vehicle toward and away from the source of power.